Manufacture of steel



G. B. WATERHOUSE. MANUFACTURE OF STEEL. APPLICATION man JULY 31. 1919.

Patented Sept. 14,1920.

2 SHEETS-SHEET I.

INVENTOR George B%ferhouse A TTORNE Y G. B. WATERHOUSE.

MANUFACTURE OF STEEL. APPLICATION HLED mu 31,1919.

PatentedSept. 14, 1920.

2 SHEETS-SHEET 2- UNI'TEDSSVSTAITES PATENT orFICE'.

GEORGE IB. wATERrtOUSE, F BUFFALO, NEW YORK.

MANUFACTURE OF STEEL.

To all whom it may concern:

Be it known that I, GEORGE B. WATER- HOUSE, a citizen of the United States, residing at Buffa1o,'in the county of Erie and 5 State of New York, have invented new and useful Improvements inthe Manufacture of Steel, of which the following is a specification.

This invention relates to improvements in the manufacture of low and low medium carbon steels and particularly steels which are high in their sulfur content including steels particularly adapted for machining, thread cutting and drawing as extensively used in the manufacture of screws, nuts and bolts in automatic cutting machines. As is well known steels as at present manufactured for use in automatic .machines are characterized by high content of sulfid of manganese which greatly improves the machining properties of the steel, causing the chips thereof to break off short in the machining operation. I A peculiarity of the low and low medium carbon steels as produced by the methods at present employed is that there is a pro- .nounced lack of uniformity in the distribu tion of the sulfur content, the latter being very irregularly distributed and forming local concentrations w ich in the cross sectional area of the stee in a sulfur print show as peculiar spotted local growths of high sulfur material in variagated effect. In the machining ofthe resulting product ,there is in consequence a corresponding irregularity .in the breaking off of the chips. By the terms low medium and low carbon steel it will be understood that steels with a maximum of about 25% of carbon are contemplated and may be as low as about .0470 of carbon. v

The improved process or method of manufacture of the present invention has for its object to produce a steel of this general character which will be improved in its physical structure particularly with relation to the sulfur distribution and consists in the addition of a deoxidizer, preferably silicon in the form of ferro-silicon and desirably in the ladle. I have found in practice that such addition materia ly improves the physical condition of the resulting steel in that substantial uni formity'in the distribution of the sulfur content is obtained. In consequence 55 of the more even distribution of the sulfid the product is materially improved and Specification of Letters Patent. Patented Sept. 14:, 1920. i -App1icatio1i filed July 31,

1919. Serial No. 314,442.

in use there will be a regular and uniform breaking off of the chips which is desirable.

Inaccomplishing this improvement in the physical condition of the steel by means of the preferred ferro-silicon addition, such ad-' dition is proportioned to the steel being made so that the maximum silicon remaining in the steel will be but the normal requirement or normal content and necessarily may not show an lncrease in the silicon content over that found in steels made without the silicon addition of my invention. 'As a result of subjecting the molten steel in the ladle to the influence of a silicon addition in acis advantageous in its application to the manufacture of improved steels for machining, threading and drawing, characterized by a high sulfur content it will be understood that my improved process is also effective and valuable in obtaining improved distribution of the sulfur in forging and special grade steels with a normal sulfur content. It will be further understood that the process of my invention is further instrumental in effecting a substantial improvement in the soundness-and physical structure of the steel in general in addition to the sulfur distribution thereby improving the workability and rollingqualities of the steel.. f

By way of illustration of the improvement in the sulfur distribution resulting from my improved process over that of the methods heretofore employed I have shown in the drawing herewith reproductions of sulfur prints taken from bars which have been produced by the ordinary method without my improved sulfur addition and also bars produced with .the sulfur addition in accordance with my invention and indicating the materialimprovements in the distribution of the sulfur content.

In the drawings Figures 1and 2 are fac? similes of sulfur prints taken from 2-}- billets of Bessemer steel produced respectively by the customary Bessemer process and by my improved process with a ferro-silicon addition to illustrate the marked improvement in the distribution of the sulfur. Figs. 3

and 4 are similar comparative facsimiles of sulfur prints taken from blooms of open hearth steel; produced respectively by the customary process and by the process of my invention.

Referring to cross sectional area of the bar illustrated in Fig. 1, the darkened portions indicate local or concentrated areas of high sulfur material as disclosed by a sulfur print of a bar of low carbon steel produced in the usual manner without the silicon addition. Low carbon steels of this general character contain carbon up to a maximum of about 0.15% and the maximum silicon content is about 0.15% while the minimum of the latter is no increase overthat found in the steels of this character without the silicon addition of my invention. The bar as illustrated in Fig. 1 is a result of the Bessemer heat which shows a ladle test analysis as follows Car .13 Man .47 Phos .097 Sul .113 Sil. in finished bar .016

Car .14

Man .48 Phos .097 S111 111 Sil. in finished bar .016

In this particular instance the silicon content indicates that although subjected to the influence of the silicon addition in accordance with my invention the normal content in the product has not been increased indicating that the silicon was slagged off. ,In the example as shown in Fig. 2 the improved result was aifected by the addition of ferro-silicon in accordance with my invention as hereinbefore described, this addition being made while the steel runs from the converter or furnace into the ladle in -the preferred mannergood results.

silicon addition in the ladle.

ment of my improved process in the produc-- tion of low carbon forging steels of normal sulfur content. The results there indicated are facsimiles of sulfur prints taken from blooms of steel produced by the basic open hearth process in connection with which my improved process produces particularly The bar as illustrated in Fig. 3 was produced by the basic open hearth process in the customary manner and the darkened portions indicate the local or concentrated areas of high sulfur material and is typical of its occurrence in steels of this character asordinarily produced. The ladle test analysis of the basic open hearth heat from which the bloom of Fig. 3 was produced is as follows Ca n; .095 Man :46 Phos .018 'Sul .065 Sil. approx .02

In Fig. 4 there is shown a facsimile of a T cordance with my invention by subjecting the molten steel produced by the basic open hearth process to the influence of a ferro- The product of Fig. 4 shows a ladle test analysis as follows l Car .11 lVIatn .50 Phos .013 S ul .045 Sil .055

Thus while I have hereinbefore' pointed out and shown by illustration that the process of my invention is particularly advantageous in producing Bessemer steels of improved properties it will be understood. that the deoxidizing addition of my improved process may with correspondingly good re'- sults be em loyed in producing steels other than by the essemer process and is particularly effective in improving the product -"of the basic open hearth process. Furthermore in the preferred use of a ferro silicon addition the latter may be proportioned to vary the silicon content of the resulting steel as may be desired. In this latter regard very good results have been obtained by my process wherein the resulting steel has shown no increase in the silicon content of the bar over the residual content of the bath. It will be further noted that by subjecting the molten steel to the influence of the ferro-silicon addition to obtain the more uniform distribution of the sulfur content the results show that the ultimate sulfur content in the product is unchanged or cortreated steel. In so far as I am aware silicon additions have never been employed in the manufacture of low or low medium carbon steels and particularly Bessemer steels, for the purpose of bringing about the .uniformity in sulfur distribution as contemplated by my improved process which as hereinbefore described successfully eliminates the variegated local growths of high sulfur material and with a material improvement in the physical structure of the resulting steel.

While I have described a preferred and particularly effective manner of carrying out the improved process of my invention it proving the physical -said silicon addition being will be understood that the specific process described by way of illustration is subject to various modifications without departing from the scope of the invention as defined in the appended claims. For instance'I may employ a deoxidizing addition of aluminum or aluminum and ferro-silicon but preferably I employ the ferro-silicon addition in the ladle as described.

Having described my invention, I claim 1. The herein described process for improving the physical structure of steels having a maximum carbon content of about 25% which consists in subjecting the molten steel to the influence of a silicon addition to effect uniformity in the sulfur distribution, said silicon addition being proportioned so asnot to materially increase the silicon content of the resulting steel.

2. The herein described process for producing steels of a maximum carbon content of about 25% which consists in subjecting the molten steel to the influence of a silicon additionin the ladle to effect uniformity in the sulfur distribution, said silicon addition being proportioned so as not to materially increase the silicon content of the resulting steel.

3. The herein described process for imstructure of Bessemer and basic open hearth steels of low carbon content which consists in subjecting molten steel to the influence of silicon addition to effect uniformity in the sulfur distribution, proportioned so as not to materially increase the silicon content of the resulting steel.

4. The herein described process of producing low carbon steel of improved quality and havin .high sulfur content which consists in su jecting the molten metal to the influence of a silicon addition to effect uniformity in the sulfur distribution, said silicon addition being proportioned so as not to materially increase the silicon content of the resulting steel. p

5. The herein described process for improving low carbon ste 31s with regard to the distribution of sulfur therein which con sists in theaddition of silicon in the ladle, substantially as' described.

6. The herein described process for. im-

proving low carbon steels with regard to the distribution of sulfur therein which. consists in the addition of silicon in the ladle, said silicon addition being proportioned whereby it will not materially increase the silicon content of the resulting steel.

7. The herein described process of producing low carbon steels of improved quality with regard to sulfur distribution which consists in the addition of a charge of ferrosilicon in the ladle to effect uniform distribution of. the sulfur content, said addition being. proportioned so as not to materially incrlease the silicon content of the resulting stee 8. The herein described process of producing low medium and low carbon steels of improved quality with regard to sulfur distribution which consists in the addition of a charge of ferro-silicon in the ladle to effect uniform distribution of the sulfur content, said addition being proportioned so as not to materially increase the silicon content of the resulting steel, whereby the latter will not exceed 0.15%.

9. The herein described process for prosists in introducing a ferro-silicon addition in the ladle to effect uniformity in the sulfur' distribution.

11. The herein described process for improving the physical structure of Bessemer steels having a maximum carbon content of 25% which consists in subjecting the molten steel to the influence of a ferro silicon addition, said addition being proportioned so as not to materially increase the silicon content of the resulting steel.

12. The herein described process for improving the physical structure of Bessemer steels having a maximum carbon content of 25% which consists in subjecting the molten steel to the influence of a'ferro-silicon addition in the ladle to eflect uniformity in the sulfur distribution, portioned whereby the resulting silicon conient of the finished'stee'l shall not exceed Intestimony whereof I have signed'my name to this specification.

GEORGE B. WAT EIbH OU SE;

said addition being prov 

